It was the latest in a series of articles that Sun colleague Julie Scharper and I have written since February about Baltimore's problems issuing and collecting bills associated with its aging water system.

We've reported on the city refunding $4.2 million to customers after an audit found widespread problems with water bills; and uncovered voluminous problems of our own, including a $100,000 overbilling of Cockeysville Middle School and a Randallstown woman who's been receiving her neighbor's bills for seven years -- both of which were fixed after our inquires.

Through it all, we've mainly focused on how the problems affect the little guy -- residential customers -- but with this latest story, The Sun analyzed how large, commercial customers have been affected.

I got the idea after reading an item in The Baltimore Brew (a very good local news site) that showed RG Steel owed $5.4 million on two water and wastewater accounts, and after listening to local activist Kim Trueheart and city Comptroller Joan Pratt mention unpaid commercial water bills at a recent Board of Estimates meeting. This begged for further reporting: Was RG Steel's unpaid bill an isolated incident, an anomaly? How many other large customers were getting away for years without paying their bills? One long-uncollected account could be an exception, but multiple accounts could be a pattern. I decided to investigate.

The city wasn't much help. City officials declined a public information act request I filed to inspect a database of city water bills, claiming they have no such database

So, with the help of Stewart, who keeps meticulous records on city water bills, and Baltimore's public data available on its website, I started analyzing companies' bills. Sun colleague Scott Calvert proved quite helpful, as he provided me with a database of city tax records, allowing me to identify some of the biggest accounts and begin typing them into the city's website to identify their bills. After manually going through 100 bills -- which we felt a fair sample size -- we found a dozen that were in arrears by $15,000 or more for at least six months. I then cross-referenced and verified the accounts with Stewart's records, which date back for nearly a decade.

Questioned about the accounts, city officials acknowledged they were aware of the long-overdue bills but declined to provide information about the scope of delinquent commercial water bills or to discuss specific accounts.

I began calling the organizations to get their responses and found out some interesting things. Though several declined to respond, those that did added depth and context to the story. When I asked chemical giant W.R. Grace about its unpaid $2.6 million water bill, officials from the company called back the next day to say they had paid $2.2 million of it. When I inquired about the VA hospital's bill, they provided me with documents to show the city had lost 15 of the federal agency's payments since 2006.

It took nearly two months in all -- along with keeping up with the daily grind of newspaper reporting -- to research and write the story. We hope you found it informative.

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